The association of non-homologous parts of chromosomes in the mid-prophase of meiosis in Zea mays

1.Association of chromosomes at pachytene in Zea mays is 2-by-2 whether or not the parts associated are homologous. 2.Evidence for non-homologous association of parts of chromosomes has been obtained from monoploids, diploids, monosomics, trisomics, deficiencies, inversions, translocations, ring-shaped chromosomes, “asynaptic” plants and so-called “B-type” chromosomes. 3.In many cases, the non-homologous association at pachytene appears to be as intimate as homologous association. 4.Non-homologous association, present at pachytene, rarely continues into diakinesis. 5.Translocations probably result from the association of non-homologous parts of chromosomes. With 51 figures in the text and plates VII–XII